The object of the invention is to improve the current conditions of "treatment" of damaged areas of certain anatomical channels or ducts.
It relates, in particular, to improving the blood circulation conditions in a damaged vascular zone, most particularly if the vessel(s) has(have) one or more aneurysms.
More particularly, it relates to improving the current conditions of treatment of aneurysms overlapping various vessels in communication therebetween, especially aortic aneurysms overlapping one or more iliac vessels, and even the hypogastric arteria.
At present, it is known to use intraluminal tubular prostheses implantable through a percutaneous intraluminal access (Seldinger approach, especially) to mitigate degeneration of or damage to anatomical channels.
These endoscopic prostheses (or endoprostheses), the object of which is to form a substitute for the duct, at least locally, frequently comprise:
a substantially non-"self-supporting" sleeve or sheath, and PA1 a tubular armature (or stent) essentially coaxial with the sheath, the armature being arranged to be radially constricted or opened out.
The armature then serves as a support for the sleeve (which therefore customarily has no intrinsic "strength" and collapses if it is not supported) and permits the percutaneous endoluminal implantation of the prosthesis, the sleeve adapting to the shape of its armature, especially to form a tube making it possible to channel a body fluid, when the armature is opened out radially.
Examples of prostheses of this type which form, locally, a substitute for the channel, are described in particular in U.S. Pat. No. 5,282,824. In WO-A-95/21592, it is even provided to attach, to a bifurcated prosthesis of this type, a tubular extension prosthesis, facilitating the positioning of the bifurcated prosthesis, thus permitting the two secondary branches thereof, which originate from the bifurcation, to be short, whilst still permitting the length of the extension to be adapted as required.
But these vascular implants introduced by the percutaneous endoluminal route may be contra-indicated in certain clinical cases, more particularly when the aneurism(s) is/are too extensive and, starting from the aorta, spread over several vessels, beyond the iliac bifurcation (outer and/or inner iliacs), and even extend as far as the hypogastric artery.
A solution may then consist in surgically implanting a vascular prosthesis for local substitution of the vessel, of the "bridging" type. But this involves "heavy" surgical intervention, in order to expose all the damaged vascular region(s), in general with thoracic and/or abdominal stripping. Such a prosthesis is described for example in WO-A-8806026 or U.S. Pat. No. 3,986,828.
However, the invention aims precisely to avoid that, thus embracing the reasons which led to the adoption of percutaneous endoluminal implants.